Energy converters are proposed as described, for example, in Japanese Unexamined Patent Publication Number 2001-69734. Such converters have been developed by extending the function of induction motors in order to realize application diversification in which a magnetism generation mechanism unit constituted by a stator that generates a magnetic field and a rotating mechanism unit having a rotor which is rotary driven or heated by the magnetic field generated by the magnetism generation mechanism unit are provided as separate independent units, and they are assembled together so as to be magnetically coupled when used as an energy converter.
The rotor of the energy converter includes a soft magnetic metal material and a good conductor surface section stacked on the metal material. Inner peripheries of a plurality of concave sections provided in the good conductor surface section magnetically form single turn coils. When a rotating or alternating magnetic field driven by an electrical power source having a predetermine frequency is exerted on the array of coils for driving the stator, a current is generated in the array of single turn coils and the current interacts with the rotating or alternating magnetic field, whereby inductive electromagnetic energy is generated. In this way the electrical energy is converted to mechanical or thermal energy.
In the mean time, while the structure in which the magnetism generation mechanism unit and the rotating mechanism unit provided as separate independent units are assembled has an advantage that the rotating mechanism unit can be separated from the magnetism generation mechanism unit and handled independently, it poses a problem that the magnetic gap length between the magnetism generation mechanism unit and the rotating mechanism unit inevitably becomes long and the energy output of the rotating mechanism unit is reduced. This is due to the structural constraint in which the rotating mechanism unit is stacked on the magnetism generation mechanism unit and the secondary induced current generated in the rotating mechanism unit is reduced as the distance of the rotating mechanism unit from the magnetism generation mechanism unit is increased.
When the magnetism generation mechanism unit and the rotating mechanism unit are integrally formed, the magnetic gap length is typically set to 1 mm or less. In the present structure in which the magnetism generation mechanism unit and the rotating mechanism unit provided as separable independent units are combined, the magnetic gap length between the magnetism generation mechanism unit and rotating mechanism unit is set, in most cases, to about 10 mm as a design parameter by taking into account, as well as current situation of induction heater rice cookers, the security requirements that the leakage does not cause any adverse and harmful effects on peripheral devices and human bodies in embodying new functional development, such as a cordless electrical power source of an underwater rotor, a new concept of heat/power characteristics in which heat source and power source of the rotor are obtained at the same time from a commercial electrical power source, and various forms of effective use of exhaust heat from devices and equipment, while maintaining the utilization efficiency.
The present invention has been developed in view of the circumstances described above, and it is an object of the present invention to provide a new electrical power transfer method usable with a large magnetic gap length. That is, it is an object of the present invention to provide an energy converter capable of securing sufficient and practicable energy output from the rotating mechanism unit by providing an efficient transfer method of effective electrical power to secondary metal load in the rotating mechanism unit and improving energy transfer performance from the magnetism generation mechanism unit to the rotating mechanism unit.
In the mean time, by positively leveraging the easy separable function of the two mechanism units, the energy converter of the present invention may be used by selecting a specialized rotating mechanism unit that satisfies the requirements of the intended purpose or environment under which it is used.